Dose-response study of the effect of a nutraceutical combining oat beta-glucan and green coffee hydroxycinnamates in overweight/obese subjects

Abstract

Obesity and its associated comorbidities (type 2 diabetes mellitus, cardiovascular disease, etc.) are a major public health concern worldwide, with prevalence of obesity affecting in Europe up to 17% of the adult population (OCED/EU 2016). Strategies to lose weight mostly relay in lifestyle changes such as restriction in food intake and increased exercise. However, these are not always easily accepted by overweight/obese subjects and their long-term efficiency is limited. Nutraceuticals and functional foods might be an alternative means to help lose weight and reduce associated cardiometabolic risk factors in affected subjects. There are different nutraceuticals/functional foods containing dietary fibre (DF) or polyphenol-rich plant extracts, but to our knowledge there is no nutraceutical combining both bioactive compounds.The objective of the present study was to assess the efficiency on different risk makers of a dietary supplement combining a soluble DF (oat beta-glucan -BG-) and a green coffee bean extract (GCBE) rich in polyphenols (PP) in overweight/obese subject.A randomized, parallel, blind, dose-response study was performed in 60 overweight/obese subjects divided into four groups (n = 15) who consumed during 6 weeks two servings per day of one of four nutraceutical formulations containing low (3 g/d) or high (5 g/d) doses of BG of different purity (35 & 70%) and a fixed amount of GCBE providing 600 mg/d PP. Food intake, anthropometry and different cardiometabolic markers were assessed at the beginning and end of the intervention.Results showed reduced levels of total cholesterol (p = 0.0001), LDL-cholesterol (p = 0.01), VLDL-cholesterol (p = 0.014) and triglycerides (p = 0.023). There were differences among both types of BG, with the 35% BG being more effective reducing lipid plasma levels than the 70% BG. Percentage of body fat significantly decreased after the intervention, the 70% BG being more efficient than the 35% BG. However, there was no effect on body weight and body mass index, which were not significantly modifiedIt can be concluded that DF and PP might have a synergistic effect reducing cardiometabolic risk factors in overweight/obese subjects.Funded by Spanish State Research Agency, project AGL2015-69986-R